Wellington, May 26 NZPA - A mining company has given more ammunition to those opposing mineral prospecting on protected land by signalling its own reservations about digging up pristine areas.

Newmont Waihi Gold (NWG), which operates in the Coromandel, headed its submission on the Government's mining proposals "leave schedule four alone", and said more detailed analysis was needed to accurately assess the conservation value of land and prove the potential value of any minerals in a given area.

Only when areas of high mineral content and lower conservation value were identified should there be discussions as to whether exploration should be allowed, it said.

Submissions closed today on a discussion document released by the Government about exploration and possible mining in the conservation estate, including some land protected under schedule four of the Crown Minerals Act. Parts of Coromandel are among the areas put forward.

Over 33,000 submissions were received by 5pm today and Energy and Resources Minister Gerry Brownlee said it would take time to assess them and decide how the Government would respond.

Labour Party conservation spokesman David Parker said in Parliament today that when a mining company was showing such caution, coupled with the public outcry mining proposals had sparked, it meant the Government was on a hiding to nothing and should back down.

Mr Brownlee said while he hadn't read the Newmont submission, he had been briefed on it and it seemed the company simply wanted the Government to tread carefully and take its time over making any decisions -- something it was doing anyway.

"(Newmont) I might also point out, is the only company that has a prospecting licence over that area at the moment -- I presume they are going to relinquish it".

He suggested to reporters earlier that Newmont may not want any competition in the areas it mines.

Green MP Catherine Delahunty also tackled Mr Brownlee on mining proposals in Parliament, suggesting the Government had got itself into a hole and should "stop digging".